Cutting drums for extracting machines used in mining are known from prior art. Herein, a frustoconical end ring is integrally joined by welds to the cylindrically shaped base body. An external step will thus result at the transition from base body to the end ring. This will cause a kind of jumping effect when extracting minerals, since the minerals must overcome this step. Particularly when extracting hard coal, a not inconsiderable quantity of minerals will be reduced to dust in an undesirable manner. Furthermore, this will cause interference in the flow of material. Finally, the end ring is subjected to very strong wear in the zone of the steplike transition from base body to the frustoconical end ring. It thus becomes necessary that the cutting drums must, from time to time, be transported above ground and sent to the manufacturer where the end rings will either be refurbished by deposition welding, should this still appear possible, or the worn-out end rings must be flame-cut and a new conical ring be welded onto the base body thereafter. These procedures are linked to considerable expenditure and to stoppages, and thus to a not inconsiderable interruption in production.
These disadvantages are not obviated even by a cylindrical construction of the end ring, while the base body is conically tapering away from the cutting face, as disclosed for example in GB Letters Patent No. 985 678.